Recent improvements in their spatial and data resolution capabilities have made digital color image processing systems attractive for a number of photoprocessing (e.g. photo-finishing) applications. In still color image photography, for example, once an image (such as that captured on color photographic film or a high resolution color digital camera) has been digitized and stored in an attendant data base, it is readily optimized for reproduction by means of photofinishing image processing software. Such image processing systems also provide for the storage and retrieval of high resolution digitized color still images for application to a variety of reproduction devices. This not only enables the photofinisher to optimize the quality of a color image print, but allows the images on a processed roll of film to be stored in digital format on a compact disc (CD), which may then be delivered to the customer for playback by a CD player and display on a television set.
One such apparatus is described in co-pending U.S. patent application Ser. No. 582,305, filed Sep. 14, 1990, entitled "Multiresolution Digital Imagery Photofinishing System," by S. Kristy, assigned to the assignee of the present application and the disclosure of which is herein incorporated. As diagrammatically illustrated in FIG. 1, such a digitizing apparatus may employ a high resolution opto-electronic film scanner 12, the output of which is coupled to a host digitized image processor (host computer) 14. Scanner 12 typically contains a very high resolution sensor pixel array (e.g. a 3072.times.2048 pixel matrix) capable of generating high spatial density-representative output signals which, when converted into digital format, yield `digitized` photographic image files from which high quality color prints may be obtained. Scanner 12 is arranged to be optically coupled with a photographic recording medium, such as a consumer-supplied 35 mm color film strip 16. Film strip 16 contains a plurality (e.g. a set of twenty- four or thirty-six) 36 mm.times.24 mm color image frames. For each scanned image frame, high resolution scanner 12 outputs digitally encoded data, representative of the opto-electronic response of its high resolution imaging sensor pixel array, onto which a respective photographic image frame of film strip 16 is projected by the scanner's input lens system.
This digitally encoded data, or `digitized` image, is supplied in the form of an imaging pixel array- representative bit map, resolved to a prescribed code width (e.g. eight bits per color per pixel), to a host processor 14. Host processor 14 contains an image encoding and storage operator through which each high resolution digitized image file is stored, preferably in a multi-resolution, hierarchical format. Such a storage format facilitates retrieval of the digitized images for reproduction by a variety of devices the resolution of which may vary from device to device, such as a low/moderate NTSC television monitor or a very high resolution, digitally driven, color thermal printer. The spatial parameters of each of the hierarchical image files into which an original 2K pixel.times.3K pixel digitized image file is encoded and stored are chosen to facilitate the implementation and incorporation of a low cost, reduced complexity frame store/data retrieval architecture into a variety of reproduction devices, thereby providing for rapid call-up and output (display or print out) of one or more selected images.
In addition to using such improved photofinishing equipment to process current day images, such as capturing original color images in digital format by way of a high resolution digitizing color camera, or scanning a roll of color negative film, there is also the demand for using such digital image processing capability to convert `old` photographs, such as dated photoprints that have been kept in a loose pile in a `shoebox`, or mounted in a family photo album, into digital format for CD storage, thereby allowing a customer to store and catalog the images on such prints for subsequent television viewing.
In consideration of this need, co-pending U.S. patent application Ser. No. 762,323, filed Sep. 16, 1991, by K. A. Parulski et al, entitled "Dual Imaging Station Scanner", assigned to the assignee of the present application and the disclosure of which is herein incorporated, describes a digitizing scanner apparatus which has the ability to automatically digitize a plurality of photoprint images which the customer brings to the photofinisher in a loosely arrayed pile or mounted in a photo-album binder, thereby allowing a photofinisher to rapidly process any number of pictures provided by the customer, irrespective of the condition or form in which the photoprints are supplied.
More particularly, FIG. 2 is an exterior perspective view, while FIGS. 3 and 4 are diagrammatic respective front and side views of the internal architecture of a dual imaging station, photoprint digitizing scanner described in the above-referenced Parulski et al application. The scanner, which is shown generally at 10, preferably comprises a housing or cabinet 11, having an upper, horizontally translatable unit 13, which supports a large area imaging station 15 for viewing an individual photoprint either by itself or retained on a page of a photo album or the like. Beneath unit 13 (and upper imaging station 15) is a lower, magazine-fed platen imaging station 17. Translatable unit 13 is supported for back and forth horizontal movement (or translation) in the direction of arrows A, either manually or by a drive motor (not shown), for the purpose of bringing a desired portion of imaging station 15 into optimum registration with viewing optics through which a photoprint is imaged onto a downstream opto-electronic image sensor.
The upper imaging station 15 comprises a transparent (e.g. glass) plate 21 upon which an individual sheet of photographic recording material, such as a photoprint, 23 may be placed in a face-down condition. Adjacent to top plate 21, translatable unit 13 has a sloped support surface 25, thereby providing, in cooperation with top plate 21, a broad area surface for supporting a large item, such as a photo album (shown diagrammatically in broken lines 27 in its open, face-down condition), so that a page of the photo album may be easily placed in direct imaging-abutment with top plate 21. A first imaging station illuminator 29 comprised of a rectangular configuration of a set of four fluorescent lamps is located beneath top plate 21, so as to provide effectively even illumination of a sheet or page of recording material that is placed face down on the top plate.
A lower portion of cabinet 11 retains a platen feed mechanism 31, which is operative to withdraw and translate a photographic print support platen from a first platen supply magazine 32 to a platen imaging station 17, and then feed the platen from the platen imaging station to a second take up platen storage magazine 34. An individual platen is preferably of a type detailed in co-pending U.S. patent application Ser. No. 760,437, filed Sep. 16, 1991, entitled "Photoprint Retaining Platen For Digitizing Image Scanner", by K. A. Parulski et al, assigned to the assignee of the present application and the disclosure of which is herein incorporated.
A photoprint-support platen as described in that application may be generally configured as diagrammatically illustrated at 18 in FIG. 5, to facilitate presentation of a photoprint to an imaging station of a photoprint imaging scanner, in a secure protected condition, while also allowing a plurality of photoprint platens to be arranged in a stacked configuration and fed one at the time to a platen imaging station, and then fed from the platen imaging station to a take up location. Preferably, a photoprint support- platen includes a photoprint-retention or mounting surface area 19 which contains a semi-tacky material 20 for removably securing a photoprint to the platen, so that the platen may be re-used with other photoprints. Adjacent to the mounting surface area are side rails 22 and the ends 26 of the platen are sloped or beveled to facilitate interleaving of multiple platens in a stack, without the mounted photoprints being contacted by an adjacent platen. One or more image parameter regions 28 are located adjacent to a photoprint mounting surface area for storing machine readable photoprint parameter information (e.g. bar codes or adjustable indicator elements). This machine readable information is detected by one or more image parameter sensors 30 located in the feed path of platen imaging station 17. The outputs of these sensors are coupled to a microcontroller 38, such as an Intel 80C196KB microcontroller which controls the operation of the scanner, including the imaging optics, to rapidly project and focus the image on the photoprint onto an opto-electronic image sensor (e.g. a high resolution CCD image sensor) 60.
The platen feed mechanism comprises a set of controllably driven pinch rollers 41 located between magazine 32 and platen imaging station 17, and a set of controllably driven pinch rollers 43 located between platen imaging station 17 and magazine 34. A controllably stepped drive motor 45 is coupled to rollers 41 and 43 by means of a conventional pulley/drive belt arrangement, not shown, and is controllably driven by the system microcontroller to rotate the pinch rollers and thereby sequentially extract a platen from a bottom slot 33 of supply magazine 32, translate an extracted platen to imaging station 17 and then translate the platen from imaging station 17 to a lower entry slot 35 of take up storage magazine 34. A second imaging station illuminator 36 comprised of a rectangular configuration of a set of four fluorescent lamps, similar to that of illuminator 29 for the first imaging station 15, is located directly above platen imaging station 17, so as to provide effectively even illumination of an individual photoprint carried by a platen that has been transported to imaging station 17.
Supported within housing 11 between upper and lower imaging stations 15 and 17 is a multi-directional image projection mechanism 50. Image projection mechanism 50 is operable to selectively project the image of a photoprint at a selected one of imaging stations 15, 17 onto an opto-electronic image sensor 60, such as a high resolution CCD sensor, the 1536.times.1024 pixel array of which is electronically scanned and digitized to obtain a digitized image, which is stored in an attendant framestore for subsequent processing. Because the sizes of photoprints may vary (typically 3R, 4R and 5R sized prints) image projection mechanism 50 includes a magnification/focussing unit 52, preferably an adjustable focus zoom lens 54, so that the photoprint image that is projected on the high resolution sensor 60 may be adjusted, as necessary, to ensure that the digitized image that is written onto a compact disc and played back on a customer's home CD player will be correctly displayed, in focus and filling the screen of a customer's television set.
Now although professional photofinishers employ standardized photoprint sizes, such as the above- mentioned 3R, 4R and 5R sizes, in practice, the actual dimensions of batches of photoprints produced by different photofinishers may vary from one another (e.g. by as much as one-quarter an inch per edge). As a result, employing a fixed magnification default setting for the zoom lens for a given photoprint size will not necessarily guarantee that the photoprint will be properly imaged on the scanner's photosensor. In order to accommodate variations in photoprint dimensions, the zoom lens is adjustable by the photofinisher, who observes the image by way of an auxiliary, relatively low resolution, monochromatic `preview` display unit to which the output of the scanner's image sensor is coupled. When the photofinisher is satisfied that the image is properly sized (and focussed) within the confines of the preview display screen, scanning and digitizing of the photoprint image as projected onto the image sensor is invoked.
A shortcoming of such photofinisher participation in the scanning of each photoprint is the fact that the preview operation is time consuming and labor intensive, and thereby results in an increased cost per processed print image. Ideally, the zoom lens magnification should be controlled by way of default settings associated with each photoprint size. Unfortunately, however, as noted above, different photoprints of a given size (e.g. 3R) do not necessarily have the same dimensions.